All HD is widescreen. The difference in picture quality you are seeing has nothing to do with the aspect ratio. Why didn't you tell us exactly what TV you have? And have you calibrated it? I have a 2000-era HDTV (Pioneer Elite Pro-610HD CRT RPTV) and it still looks amazing, but I keep it well adjusted. My newer LCD HDTVs (a Sony and a Toshiba) look crisper, though, because they're fixed-pixel. I suspect that is the difference you are noticing.
All HD is widescreen. The difference in picture quality you are seeing has nothing to do with the aspect ratio. Why didn't you tell us exactly what TV you have? And have you calibrated it? I have a 2000-era HDTV (Pioneer Elite Pro-610HD CRT RPTV) and it still looks amazing, but I keep it well adjusted. My newer LCD HDTVs (a Sony and a Toshiba) look crisper, though, because they're fixed-pixel. I suspect that is the difference you are noticing.